Impact means for power-operated pipe wrench



Oct. 25, 1955 w. c. KLITZKE 2,721,491

IMPACT MEANS FOR POWER-OPERATED PIPE WRENCH Filed March 50, 1954 2Sheets-Sheet 1 0C];- 25, 1955 w c KUTZKE IMPACT MEANS FOR POWER-OPERATEDPIPE WRENCH Filed March 50, 1954 2 Sheets-Sheet 2 Unite 7 IMPACT MEANSFOR POWER-OPERATED PIPE WRENCH Application March 30, 1954, Serial No.419,658

10 Claims. (Cl. 8152.3)

This invention relates to a hammer breakout and more particularly to animpact wrench device for breaking the tool joints of an oil well drillpipe line.

In a drill pipe line, such as is employed with an oil well drillingapparatus, the threaded tool joints often become so tightly screwedtogether that it is exceedingly diflicult to break them loose.Heretofore, various forms of impact devices have been devised to effectloosening of a tight joint, and the present invention contemplatesimprovements over such known devices in that the joint may be broken inan eflicient and rapid manner and without undue effort upon the part ofthe operator.

A principal object of the present invention is to provide novel meansfor imparting powerful impact blows to a conventional drill pipe toassist in breaking loose the tool joints which couple the pipe sections.Another object is to provide an improved impact wrench having novelimpact imparting or hammering mechanism. Yet another object is toprovide an improved hammer breakout for a tool joint. A further objectis to provide improved resilient means in which energy is stored duringretraction of the hammer and for imparting rapid forward motion to thehammer when the latter assumes its retracted position. Still anotherobject is to provide an improved impact wrench of the fluid operatedtype and having embodied therein improved trigger mechanism foreffecting release of the hammer when the latter assumes its retractedposition. A still further object is to provide an improved wrenchmember. Further objects and advantages reside in the detailedconstruction of the wrench structure, which is designed for simplicity,economy and efliciency. These and other objects will hereinafter becomeapparent from the following description.

In the accompanying drawings there is shown for purposes of illustrationone form which the invention may assume in practice.

In these drawings:

Fig. l is a plan view of an illustrative form of the improved hammerbreakout with the latter shown in association with a drill pipe line ofa conventional rotary oil well drilling apparatus.

Fig. 2 is a side view of the hammer breakout and drilling apparatusshown in Fig. 1.

Fig. 3 is an enlarged longitudinal vertical section taken on line 33 ofFig. 1, illustrating structural details of the hammer breakout andshowing the hammer in forward blow-striking position.

Figs. 4 and 5 are vertical sections similar to Fig. 3, showing movingparts in different positions.

Pig. 6 is an enlarged cross section taken on line 6-6 of Fig. 4.

Fig. 7 is an enlarged horizontal section taken on line 7-7 of Fig. 2,showing details of the wrench.

In this illustrative embodiment of the invention, as shown in thedrawings, the improved hammer breakout or impact wrench device isgenerally designated 1 and is shown associated with a drill pipe line 2of a conventional oil well drilling apparatus, generally designatedStates Patent C) 2,721,491 Patented Oct. 25, 1955 3. The drillingapparatus may assume various forms and herein includes a rotary table 4provided with a conventional slip bowl 5 having slips for holding thepipe line suspended in a well during the joint breaking operation. Thedrill pipe line includes pipe sections 6 coupled together at 7 by usualthreaded tool joints. The hammer breakout or Wrench device 1 may engagean upper pipe section above the tool joint in adjacency to the latter,as shown in Fig. 2, and the pipe line below this tool joint is heldsuspended and against rotation by the slips of the slip bowl of therotary table, in a well-known manner. Evidently the hammer breakout maybe used in breaking joints of other types of equipment.

The hammer breakout or wrench device 1 comprises a wrench member 10having a polygonal opening 11 through which the drill pipe line extendsand the pipe sections are polygonal in cross section substantially tofit the wrench opening (Figs. 1 and 7). The wrench body has a laterallever arm 12 and a swingable jaw or gate 13 is pivoted at 14 on thewrench body and is held in closed position by a releasable pin 15. Thelever arm desirably projects laterally from the wrench body at the sidethereof opposite from the gate. This jaw or gate enables readyattachment of the wrench to the upper pipe section above the tool jointand as the wrench is rotated or turned the walls of the polygonalopening 11 may grip the polygonal surface of the drill pipe to rotatethe latter therewith.

Mounted in a suitable manner at one side of the rotary table of thedrilling apparatus is an upright support 17 (Figs. 1 and 2) to whichvertically spaced brackets 18 are secured, and these brackets support avertical pivot pin 19. Pivotally mounted on this pivot pin between thebrackets is a horizontal arm or arm-like support 20 desirably in theform of an I-beam and a trolley 21 has rollers 22 which may roll alongthe upper surface of the bottom flanges of the arm longitudinally to thelatter. This trolley carries a horizontal pin or pivot rod 23 on which aswivel member 24 is pivotally mounted to swing laterally and rotativelysuspended from this swivel member on an upright axis is a swiveled eye25. This eye is connectible to a hook 26 on the body 27 of the hammerbreakout or wrench device so that the latter is held flexibly suspendedfrom the trolley and is movable with the latter, thus to permit properpositioning of the wrench with respect to the drill pipe. If desired,the support 17 may be vertically adjustable to vary the elevation of thewrench device.

The hammer breakout or wrench device has secured to its body 27 alignedhorizontal cylinders 28 and 29, the former being a hammer cylinder andcontaining a hammer or striking plunger 30 and the latter cylinder beinga fluid cylinder and containing a reciprocable piston 31. The inner orfront cylinder 28 has a front head plate 32 secured, as by screws, to aflange 33 on the forward portion of the cylinder 28 and the latter has arear head 34. The hammer 30 has a reduced striking bar portion 35 whichpasses through an axial opening 36 in the front cylinder head plate 32into contact with a vertical impact surface 37 on the arm 12 of theWrench member (Figs. 1 and 3). Thr'eadedly secured at 39 to the hammer30 (Fig. 3) is a rearwardly extending coaxial retracting rod or bar 40which extends rearwardly through an axial opening 41 in the Theretracting mechanism for the hammer for mov ing the latter rear-wardlyin opposition to the resilient mechanism may assume various forms andherein desirably comprises a piston rod 43 secured to the piston 31 andextending forwardly through a suitable packing or gland 44 carriedbyafront head 45 of the cylinder 29, this head being secured, as by screws,toa rear plate 46in turn secured, as by screws, to the body 27 of thehammer breakout. Fluid conduits 47 and 48 are connected to the oppositeends of the cylinder 29 at opposite sides of the piston 31 and throughwhich pressure fluid, desirably a liquid under pressure, may be suppliedforeffecting, reciprocation of the piston. Any suitable valve means maybe provided for controlling fluid flow in these conduits.

The piston-rod43-carries at its forward end a suitable triggermechanism; which herein' desirably comprises a spider or yoke 50threadedly secured at 51 to the forward' end of the piston rod and thisspider has four equally-spaced bifurcated radial arms 52, the furcationsof which carry pivot pins 53 onwhich fingers or leverlike latches 54 arepivotally mounted. These latches are movable at their forward ends intoan annular groove 55 at the rearward end portion of the retracting bar459 and are yieldingly held in grasping relation with respect to the barin contact with the rear wall of the groove by an expansible spring ring56 which engages the forward portionsof the latches in the manner shown.The rear plate 46 on the body 27 has a conical opening 57 and when thehammer 30 and the piston 31 approach their retracted positions, as shownin Fig. 5, the fingers or latches attheir rearward ends engage thetapered walls of this conical opening so that as the piston 31 continuesto move rearwardly the forward portions of the arms are swung apart torelease the retracting bar from their grasp, and the resilient energystoring mechanism embodying the coil spring 42 then drives the hammer 30rapidly forwardly in the cylinder 28 to deliver a sharp blow to thelever arm 12 of the wrench member, thereby to break or loosen the tooljoint. In the event one blow does not loosen the joint, the hammer maybe quickly retracted and then again released to strike an additionalblow, in an obvious manner.

Evidently the hammer breakout or wrench device may be supported invarious= conventional manners other than that disclosed, and the hammermay be retracted against a resilient opposing pressure by various othermeans, either manual or automatic. Under certain conditions, compressedair, a resilient rubber-like mass or other equivalent compressible meansmay be employed in the cylinder 28 in lieu of the spring 42 so that theexpansive action of the air pressure or other resilient means may drivethe hammer forwardly, when the trigger mechanism is released, to strikeits blow. While the wrench member is shownseparate from the body of theimpact device, it is obvious that the wrench may be loosely supportedfromor otherwise connected to the impact device in any suitable manner.

The general mode of use of the improvedhammer breakout or wrench devicewill be clearly apparent from the description given but to summarize,the hammer breakout may be suitably positioned by adjusting movements ofthe swinging: arm and the trolley 21 properly to locatev the strikingbar of the hammer with. respect to the wrench lever 12 after the wrenchmember has been moved. into place, as shown in- Figs. 1 and 2, and. the

der' pressure may then be supplied to the front end of the cylinder 29to effect movement of the piston'iai rearwardly from the positionshownin- Fig; 4, and the" trigger mechanism which grasps the retracting barmoves the hammer rearwardly against the'actio'n of the energy" storingspring 42, further highly compressing the latter. When the piston 31reaches the position shown in Fig. 5 the latches 54 engage the taperedwalls of the bore 57 and as the piston continues to move rearwardly thelatches are released from their grasp on the retracting bar and the thenfreed hammer is rapidly driven forwardly in the cylinder 28 to impart apowerful blow to the lever arm 12 of the wrench member 18, therebyimparting apowerful rotative force to the upper pipe section to effectbreaking or loosening of the tool joint. After the blow has beendelivered to the wrench member, fluid under pressure may be supplied tothe rear end of the cylinder 29 to move the piston 31 forwardly and whenthe trigger mechanism reaches the position shown in Fig. 4' theretracting bar 40 is again grasped by the latches 54. When the piston 31is again moved rearwardly the hammer 30 is retracted and, if desired, anadditional blow or blows may be imparted to the wrench to. break orloosen a stubborn joint.

As a result of this invention an improved hammer breakout or impactwrench device is provided whereby a powerful impactblow may betransmitted to the upper pipe section above the tool joint thereby toimpart a powerfuLrotative force to the upper pipe section to break orloosen the joint. By the provision of the resilient energy storingmechanism for driving the hammer forwardlyand the power operatedretracting mechanism for retracting the hammer the latter may be quicklyretracted and then when freed from the retracting mechanism suddenlydrivenforwardly with atremendous impact force. The improved triggermechanism associated with the hammer and the piston-of the powercylinder enables efii'cient retraction of the hammer and quick releaseof the hammer y when the latter assumes its fully retracted position.The

device is not. only simple and-rugged in design but it is also eflicientand reliable in operation, well adapted for its intended purpose; Theseand other advantages of the invention willbe. clearly apparent to thoseskilled in the art.

While there is in this application specifically described one form whichthe invention may assume in practice, it will be understood that thisform of the same is shown for purposes of illustration and that theinvention may be modified and embodied in various other formswithoutdeparting from its spirit or the scope of the appended claims.

What- I claim as new and desire to secure by Letters Patent is:

1. In an impact wrench device, a support, a hammer mechanism carried bysaid support and including a movable hammer for imparting an impact blowto a wrench member to be rotated, a power device carried by said supportat the rear end thereof for retracting said hammer, resilient means forsuddenly driving said hammer forwardly when said hammer reaches itsretracted position and is freed from said power device, a triggermechanism operated by said'power device for connecting said hammer tothelatter for retraction thereby, and means actuated by rearwardmovement of said hammer for releasing said trigger mechanism when saidhammer assumes its retracted position to free said hammer for forwardmovement, said power device having a power actuated element extendingaxially forwardly and said trigger mechanism comprising areleasablelatch carried at the front end of said power actuated element.

said h'arr'i'mer', and means in which energy is stored asa result; ofsuchretraction of said hammer by said poweroperated means for impartinga sudden forward driving force to said hammer when the latter is freedfrom said power operated means.

3. An impact wrench device as set forth in claim 2 wherein said energystoring means comprises compressible resilient means which is highlycompressed during retraction of said hammer by said power operatedmeans, and means is provided for suddenly freeing said hammer when thelatter assumes its retracted position to cause said compressed resilientmeans to drive said hammer forwardly.

4. An impact wrench device as set forth in claim 2 wherein a triggermechanism is provided for connecting said hammer to said power operatedmeans, and means is providedfor releasing said trigger mechanism to freesaid hammer from said power operated means when said hammer assumes itsretracted position.

5. A blow-striking device for imparting a rotative blow to an element tobe rotated comprising a hammer, a power operated means, releasable meansfor connecting said hammer to said power operated means to enable thelatter to retract said hammer, means for releasing said connecting meansto free said hammer from said power operated means when said hammerassumes its retracted position, and means for driving said hammerforwardly when said connecting means is released as aforesaid, saidpower operated means being located rearwardly of said hammer drivingmeans and including a forwardly extending element at the front end ofwhich said releasing means is carried.

6. A device as set forth in claim 5 wherein said hammer-driving meanscomprises a mechanism in which energy is stored as said hammer isretracted by said power operated means, and said energy storingmechanism drives said hammer forwardly when the latter is freed by saidreleasable connecting means from said power operated means.

7. An impact wrench device comprising a wrench member engageable with anelement to be rotated, and means for delivering a powerful impact blowto said wrench member comprising a reciprocable hammer, means forguiding said hammer during its reciprocable movement, compressibleresilient means for opposing rearward movement of said hammer, means forretracting said hammer against the action of said resilient means, saidresilient means when said hammer assumes its retracted position drivingsaid hammer forwardly by its expansive action to cause said hammer toimpart a powerful blow to said wrench member, a trigger mechanismoperatively associated with said retracting means for connecting thelatter to said hammer, and means actuated by rearward movement of saidhammer for releasing said trigger mechanism when said hammer assumes itsretracted position to free said hammer from said retracting means, saidretracting means located rearwardly of said hammer guiding means andincluding a rod extending forwardly, said trigger mechanism including areleasable latch carried at the front end of said rod.

8. An impact wrench device as set forth in claim 7 wherein saidretracting means also comprises a cylinder coaxial with said guidingmeans rearwardly of the latter and a fluid actuated piston reciprocablein said cylinder, said forwardly extending rod being the rod of saidpiston.

9. In a device of the character disclosed, a wrench member having a bodyprovided with an opening through which an element to be rotated isadapted to extend, said body upon turning of the wrench member engagingthe element to be rotated for rotating the latter therewith, said bodyhaving a lever arm projecting laterally from one side thereof andadapted to receive the rotative forces for turning the wrench member,said lever arm having a plane impact-receiving surface, andimpact-imparting means disposed with its longitudinal axis atsubstantially right angles to said impact-receiving surface fordelivering an impact blow to said surface to turn said lever arm therebyto effect turning of said wrench member.

10. In an impact wrench device, a support, a hammer mechanism carried bysaid support and including a movable hammer for imparting an impact blowto a wrench member to be rotated, a power device carried by said supportfor retracting said hammer, resilient means for suddenly driving saidhammer forwardly when said hammer reaches its retracted position and isfreed from said power device, said power device comprising relativelyreciprocable coacting cylinder and piston elements arranged coaxiallywith said hammer at the rear end of said support, releasable meanscarried by one of said elements at the forward end thereof forconnecting said hammer for movement with a reciprocable one of saidelements into its rearmost position and releasable to free said hammerfrom said power device to permit said resilient means to drive saidhammer forwardly as aforesaid, and means for supplying an operatingmedium to said cylinder element to effect relative reciprocation of saidelements.

References Cited in the file of this patent UNITED STATES PATENTS1,464,824 Kollock et al Aug. 14, 1923 1,775,343 Greve Sept. 9, 19302,470,891 Hammers May 24, 1949 2,492,840 Bugg Dec. 27, 1949 2,501,542Sheldon Mar. 21, 1950 FOREIGN PATENTS 658,284 Great Britain Oct. 3, 1951662,409 Great Britain Dec. 5, 1951

